KP Astrology Explained clearly how to use retrograde planets (వక్ర గ్రహలు) at the time of prediction. Retrograde planets considered as important in KP rules. For example if you are looking when I will get marry horary chart. You need to look on 7th cuspal sub lord and need to analyze 3 parameters.
7th Cusp Sub Lord – If retrograde after that planet direct in transit event will takes place.
7th Cusp Sub Lord – Star – If retrograde event will not takes place.
7th Cusp Sub Lord of the Sub – If retrograde after that planet direct in transit event will takes place.
The same rule you can look for job (10th cusp), abroad fly (12th cusp) depends on the purpose.